I don't know if I understand your question correctly.
LoWe allows you to run X server. Upon X several window managers like Unity, IceWM, etc. are running.
You will always need a native X server with a window manager running on Ubuntu on Windows coordinated by LoWe to use GUI applications. This is how it works. LoWe is not an X-call interpreter, it emulates Linux kernel syscalls.
I hope I correctly understood your question.
I don't know if I understand your question correctly. LoWe allows you to run X server. Upon X several window managers like Unity, IceWM, etc. are running. You will always need a native X server with a window manager running on Ubuntu on Windows coordinated by LoWe to use GUI applications. This is how it works. LoWe is not an X-call interpreter, it emulates Linux kernel syscalls. I hope I correctly understood your question.